Subject: Re: [RFC] Reliable video POSTing on resume (was: Re: [ACPI]
	Samsung P35, S3, black screen (radeon))
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Pavel Machek <pavel@ucw.cz>
Cc: Jon Smirl <jonsmirl@gmail.com>, ncunningham@linuxmail.org,
       Carl-Daniel Hailfinger <c-d.hailfinger.devel.2005@gmx.net>,
       ACPI List <acpi-devel@lists.sourceforge.net>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Sad, 2005-02-05 at 09:35, Pavel Machek wrote:
> Rumors say that notebooks no longer have video bios at C000h:0; rumors
> say that video BIOS on notebooks is simply integrated into main system
> BIOS. I personaly do not know if rumors are true, but PCs are ugly
> machines....
> 							

A small number of laptop systems are known to pull this trick. There are
other problems too - the video bios boot may make other assumptions
about access to PCI space, configuration, interrupts, timers etc.

Some systems (intel notably) appear to expect you to use the bios
save/restore video state not re-POST.

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